1. Field of the Invention
The present invention relates to irrigation systems, particularly it relates to flood irrigation. In irrigating a field by flowing water through a furrow, it has been found in the art that after a period of time, under flood irrigation, the speed with which the water percolated downward increases with time. Thus, as the soil becomes saturated with the water there is little or no further movement away from the water source since the water will move downward in the saturated soil faster than it will move further forward into the fields. Consequently, controlled surge irrigation systems have been proposed in which the water is dispensed to the furrows for a pre-selected period of time which is less than or equal to the time it takes for the soil to be saturated. The water is then turned off for a period of time for the water to recover from the initial water surge. During the second dispensing of water, the water will travel further along the field before the soil is saturated due to the fact that the water initially will travel faster down the already wetted and slick furrow. The procedure will then be repeated periodically until the water has travelled the desired distance in the field to be irrigated. The present invention relates to an improved method of performing surge irrigation in which the amount of piping and the number of surge valves required is reduced. Specifically, according to the present invention a surge valve is provided centrally underground within the main water supply and has the ability to periodically send water to multiple fields from a central control point.
2. Description of the Prior Art
Flood irrigation has been used for years to irrigate cultivated fields. In recent years there has been a more efficient way of controlling flood irrigation by the so-called surge irrigation using a surge valve such as Waterman Surge Valve H.P. 500. The surge irrigation is accomplished by off timing the flow of the water on a field to move the water forward faster than it will soak downward. Such surge irrigation results in a conservation of water and a reduction of power cost. A problem with the conventional surge irrigation systems is the need for multiple pieces of equipment to switch from one field to another and additional surface pipe to supply water to the center of the field to be watered. Moreover, it was necessary to set the surge valve in the center of the surface watering pipeline at equal distance from the left and right ends of the field to be watered.